Bolt patterns, and centerlock profiles

[Storbeck]

I'm wondering what bolt patterns most teams use, if there is any sort of standard. Also, the teams that use centerlock wheels, what sort of profile they use, and what pattern for the drive pins. It sounds like there are basically two somewhat standard patterns for smaller centerlock wheels, the van Demen (Spelling?) used on small formula cars of that make, and the Stohr used on the stohr dsr. Does anybody use one of these two?

Andy

[Storbeck]

I'm wondering what bolt patterns most teams use, if there is any sort of standard. Also, the teams that use centerlock wheels, what sort of profile they use, and what pattern for the drive pins. It sounds like there are basically two somewhat standard patterns for smaller centerlock wheels, the van Demen (Spelling?) used on small formula cars of that make, and the Stohr used on the stohr dsr. Does anybody use one of these two?

Andy

[Z]

Andy,

If you are going to make your own centrelock axles/wheels then don't use drive pins. They allow a small amount of movement during severe torque reversals and eventually the mating surfaces fret, or the nut comes loose. http://fsae.com/groupee_common/emoticons/icon_frown.gif Likewise any sort of parallel splines. (Well, with a big enough nut, tightened up enough, and with a good nut-locking system, you can get away with it. But it is not the best way to do it.)

Instead use "face splines". http://fsae.com/groupee_common/emoticons/icon_wink.gif

Or 3 or 4 bolts on ~100mm pcd, since quick wheel changes aren't essential.

Z

[rjwoods77]

Use sprint car splined centers. They use an involute spline which is nice. You can buy the retaining nuts, spacers, etc.. The common 600cc sprint car spline uses a 1.75 major od with 27 splines. I have all the specs of the splines if you really need them.

[BryanH]

Andy re centrelock wheels, research "Principles of the Rudge-Whitworth Centre-Lock Wire Wheel"

seemingly simple solutions have some clever physics going on under the surface.....

IMHO Porsche GT3 cup car has a simple, reliable wheel attachment setup, pin drive with a relatively small nyloc nut. go and check one out. Dynoed a friends FD RX7 yesterday and it had a weird scraping noise coming from the rear brakes when I driving to the workshop....All the wheel nuts were loose! nothing is safe from passion fingers.